India struggles to perfect art of monsoon forecasting

Krittivas Mukherjee and Ratnajyoti Dutta of Reuters report from New Delhi: Technological wizardry may have improved forecasting of the crucial monsoon rains in India, but success still remains, at best, patchy, making it tough for farmers to plan crops and meet demand in the trillion-dollar economy.

Jitendra Prakash / Reuters

A man rides a cycle rickshaw through a street amid heavy rain showers in the northern Indian city of Allahabad on May 18. This year, the country has forecast a normal monsoon.

This year, the country has forecast a normal monsoon. In theory, that should mean higher farm output, which could tame food prices and help persuade the government to ease curbs on rice and wheat exports, benefiting other Asian economies that are struggling with food shortages.

In reality, since 1994, India's weather office has only managed to forecast the June-September monsoon outcome correctly five times, discounting an error band of +/-5 percent, while on seven occasions the extent of error touched double digit, Deutsche Bank analysts said in a research report.

From the world's top producer and consumer of a range of commodities like sugar and grains, such uncertainties have huge implications for global commodities markets.

For about 600 million Indians who are dependent on farming, there is a direct correlation between ample rains and their disposable incomes, explaining the host of superstitions that survive around bringing rains, such as women ploughing fields naked and frog "marriages".

"Current capabilities to forecast monsoon are not sufficient," Shailesh Nayak, the top civil servant in the ministry of earth sciences which controls the country's weather office, told Reuters.

A woman fills her pitcher with drinking water from a "virda", a small opening made by villagers manually to collect water, from the dried-up Banas river at Sukhpur village, north of the western Indian city of Ahmedabad May 12, 2011. At least 30 virdas have been dug up by villagers in the river. Villagers walk two and a half kilometres to draw drinking water from them, and they say it takes 30-40 minutes to fill a five-litre jar. Occasionally the villagers get their supply of drinking water from municipal tankers but most of the time they depend on the virdas before the monsoon arrives in the region. This year, the country has forecast a normal monsoon. Picture taken May 12, 2011. REUTERS/Amit Dave (INDIA - Tags: ENVIRONMENT SOCIETY)

Back in 1886, when the India Meteorological Department made its first monsoon forecast, the pace of melting of snow on the Himalayas was used to predict the timing and quantity of rains.

Now, Indian officials use complicated statistical models aided by super computers and satellite data to predict weather patterns. But as recently as 2009 the weather office got its monsoon forecast completely wrong.

"Using a statistical approach is a good guide to a seasonal outlook, but this approach tends to limit any statistical anomaly of the past by minimising the possibility that it could happen again," said Michael Ferrari, vice president, Weather Trends International.

So do India's forecasting methods lag those in the western world? To say yes would only be partially true.

Among all the major global economies, India's dependence on seasonal rains is unparalleled. It is also the only country to quantify the amount of rains expected -- aimed at allowing farmers to plan crops better but making it more susceptible to errors.

"A correct forecast of rainfall quantum over a particular area is still a challenge," said Nayak.

Amit Dave / Reuters

Women carry pitchers filled with drinking water that they drew from a well near the banks of the dried-up Dharji lake at Dharji village, west of Ahmedabad, on May 14. The village has six wells but only one of them has water. In the afternoon women from the village must wait for two to three hours for the water level to rise before they are able to draw water. Also, it is a two to three kilometres' walk to the well. Authorities say water levels have dropped due to a decrease in rainfall.

Forecasts also have political implications given the farm sector employs two-thirds of India's 1.2 billion people -- the single largest factor influencing politics, even though it only makes up 14.6 percent of the economy.

A normal monsoon brings a boost to farm incomes and so to demand -- for cars, motorcycles, consumer goods and even gold, which is used for investment.

A failed monsoon can also send shockwaves into international markets. In 2009, the country suffered its worst drought since 1972 after initial forecasts had been for normal rains. India had to import sugar, driving global prices to their highest in three decades.

"The sensitivity around the Indian monsoon has financial repercussions both within India and abroad. Particularly with respect to sugar, which has become a much more important global commodity in light of higher oil and (corn derived) ethanol prices," Ferrari said.

Rupak De Chowdhuri / Reuters, file

Villagers solemnise a frog marriage at Madhyaboragari village, east of Siliguri in this July 19, 2009 file photo. The frog marriage is a traditional ritual to appease the gods in order to bring in rain and ensure a good harvest.

But for many of India's farmers, the monsoon is still about studying wind direction and observing cloud patterns, with a dose of superstition thrown in.

In eastern India, it is not unknown for farmers to ask their unmarried daughters to plough parched fields naked to embarrass the weather gods into bringing rains.

Elsewhere, customs such as marrying off two frogs and holding community feasts are followed in the hope of rains.

According to Indian weather officials, improving forecasting methods is a work in constant progress.

"We have to bring in uncertainties of monsoon forecast to forefront to better understand complexities involved with the business of weather prediction," said Ajit Tyagi, India's weather office chief.